Extrusion dies are used to form polymer films, laminates, and the like. An extrusion die forces a molten polymeric material through a gap defined by spaced apart lips to form the extruded film, typically called an extrudate. The extrudate is cooled as exits that gap and is collected by a collector or device for packaging into a form suitable for later processing. The size of the gap, among other factors, can define the thickness or gauge of the extrudate. A thermally responsive lip adjustment assembly can be used to help control both width-wise and machine-direction variations in extrudate gauge. Lip adjustment assemblies typically include a translator and a rod coupled to the translator. The translator is configured to expand and contract in response to temperature changes. The rod to moves with expansion and contraction of the translator. Movement of the rod, in turn, causes the lip to move, thereby adjusting the gap dimension as needed. Movement of the translator can be controlled with a control system during processing in response to gauge measurement at or downstream from the gap. The translator can also be manually adjusted as needed to adjust the gap dimension.
Repair and maintenance of typical lip adjustment assemblies can be complex and time consuming. Disassembly procedures require the removal of a number of parts to access internal parts of the lip adjustment assembly intended for repair or replacement. For example, there are typically a number of parts that must be removed to access the translator and rod, such as cover plates, retainer bars, wire boxes, etc. Furthermore, these parts may be obstructed by other components of the extrusion die, collector devices near the gap. After the intended repair or replacement is finished, reassembly is just as complex and time consuming. The result is significant time lost due to maintenance that would otherwise be used to manufacture extruded films. Time lost increases maintenance costs, increases product costs, and has a negative impact on the return on investment in the extrusion die, all of which are generally undesirable.